The Ultimate Headlight Bulb Guide

We receive many inquiries every day where customers say they want completely white light and it should be as powerful as possible. The problem here is that it is a “contradiction,” similar to asking for a warm cola that is cold, if we may put it a bit bluntly 

When we talk about a standard halogen bulb installed in a car, whether it is H7, H1, or H4, there are just limitations in the basic technology if we take a completely standard one.

Blue/white light from a halogen bulb

This can be done in two ways. The most common is to color/coat the bulb with a white/blue color, which changes the color of the light, but when you do this, it simply means that the light output is limited – see it as if you are holding a piece of colored foil in front of the bulb – there will always be a “light loss” in this way.

Another method is to add a bit of xenon gas into the halogen bulb, which can give a slightly whiter light than halogen gas allows.

There are “2” types of bulbs that provide significantly nicer light than the dull standard halogen bulbs.

1. A bit whiter light – Osram Cool Blue / Philips White Vision – this type of bulb gives a “slightly more” white light than a standard halogen bulb
2. Significantly whiter light – GP Thunder 7500K bulbs have repeatedly been the test winner for the “nicest” light on the market, still legal and E-marked
3. GP Thunder 8500K bulbs are not legal, as they are simply too colored in the glass, almost shading into purple

Are there other parameters that affect the color of the light? YES! There actually are. The shape of the headlight reflector can determine how the light is reflected, as well as how the light is projected out by lens headlights – there is not much you can do, but you may experience that a bulb changes the color of the light significantly from one headlight to another.

Basic rule – The whiter/bluer light you get with a halogen bulb, the “less” light will come out on the road

Can you get halogen bulbs with better/more powerful light?

Yes, you can

What color light gives the best light on the road?

Basically, you try to hit the “daylight” temperature, which is about 5500K – but original Xenon is usually around 4300K – in fact, a “whiter” light (higher kelvin) gives worse light in poor visibility, in fog and rain, yellow light will actually break through best, which is why you can argue against it always being an advantage for the light output to be as white as possible, and it can also worsen visibility while driving.

Our bulb recommendations

Best light: Osram Night Breaker Intense

Middle ground: Osram Cool Blue

Nicest light: GP Thunder 7500K